The trade off with skipping SZ30 is what you need to look at…
If Japan did a FULL consolidation in SZ30, then you have 2 TRN instead of 1 as Japan at the start of J1. That is a nice advantage from the start for Japan.
If the Allies Consolidate, do the same as Japan… Do Pearl Ultra-Light, take China, take Bury. Build TRN and some INF. Consolidate the Japan Fleet into 2 combat groups, with a straggler unit or two.
What does UK do then?
Run Away to the Atlantic? 4 turns that the Axis gets to largely ignore those forces
Protect Australia? The US better be spending money in the Pacific, or the UK Fleet is going to get sunk in short order with minimal Japan losses.
Shield/Counter Egypt? You are going to run out of land units to transport in short order, leaving a UK fleet with no real threat in the Indian Ocean.
Against the SZ30 Unification, Japan simply builds TRNs (with the remainder as land units) and groups their starting fleets into 2 major clusters. Anchored with 2 BB’s and 2 AC’s plus SIX starting FIGs, the UK fleet is pretty much worthless as an attack force against the Japs. The only concern for Japan is a merge of the UK and USA forces… and a “fodder TRN” build J1 pretty much blocks that effort from the start.